Flexible display has been more and more widely used in our lives due to its characteristics of light weight, thin thickness, bendable and even rollable properties, good mechanical property, and so on. A flexible display device is generally manufactured on a flexible carrier. Its bendable property also brings great challenges to its design and manufacture. Indium-Tin-Oxide (ITO) electrode is generally used as an anode in the flexible display device to implement pixel display.
FIG. 1 is a plane view of a pixel unit of a display substrate in the prior art. FIG. 2 is a cross-sectional view of the pixel unit of the display substrate in FIG. 1 taken along line A-A. As shown in FIGS. 1 and 2, the display substrate comprises a base substrate 9, a thin film transistor 8 formed on the base substrate 9, and a pixel electrode 7 formed on the thin film transistor 8. The thin film transistor 8 comprises a gate electrode 1, a gate insulation layer 2, an active layer 4, a source electrode 31 and a drain electrode 32, which are sequentially arranged. A passivation layer 5 is formed on the source electrode 31 and the drain electrode 32, and the pixel electrode 7 is formed on the passivation layer 5. A via 13 is provided in the passivation layer 5. The pixel electrode 7 is electrically connected with the drain electrode 32 through the via 13, which allows the thin film transistor 8 to control the pixel electrode 7 to implement pixel display.
However, in the structure of the display substrate in the prior art, as shown in the plane view of FIG. 1, since the via 13 electrically connecting the drain electrode 32 with the pixel electrode 7 has a very small area, contact area between the drain electrode 32 and the pixel electrode 7 is very small. If the pixel electrode 7 is broken, the pixel electrode 7 and the drain electrode 32 will be disconnected, i.e., electrical connection therebetween cannot be maintained any longer. In this case, the pixel cannot be driven to display normally by an external signal, which reduces display quality.